Evidence of suppression of ITG-instability in the radiatively improved mode in TEXTOR-94

Characteristics of the toroidal ITG-instability are analysed for conditions of the L-mode and the radiatively improved (RI) mode triggered in TEXTOR-94 by puffing of neon. Analysis is performed for experimentally measured profiles of the plasma parameters and densities of impurity species. It is shown that in the Pi-mode the anomalous transport induced by this kind of instability is reduced significantly in a large part of the plasma volume. This is an important channel of the energy confinement improvement. The role of the radial electric field is envisaged.